JPH054006Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a stage apparatus used for manufacturing a semiconductor device, such as an electron beam lithography apparatus or a reticle defect inspection apparatus.

[Technical background of the invention and its problems] Conventionally, for example, in a reticle inspection device,
As a stage device for mounting a reticle, one shown in FIG. 4 is known. In other words, 1 in the figure is the X, Y stage, and this X, Y stage 1
A pair of laser mirrors 2 and 3 for position measurement are provided in an L-shape on the top surface. A rotary stage 4 is provided on the upper surface of the X, Y stage 1, and a reticle 6 held by a holder 5 is fixedly placed on the rotary stage 4. The holder 5 is automatically loaded and unloaded onto the rotary stage 4 by an automatic supply device (not shown). Further, each corner of the rotation stage 4 is formed into an arc shape, and a rotation receiving roller 7 is rolled into contact with each corner. The rotation receiving rollers 7 are rotatably arranged on the X, Y stage 1,
The rotary stage 4 is rotatably supported.

On the other hand, a protruding piece 8 is provided on one side wall of the rotary stage 1, and the tip of a piston 10 of a drive mechanism 9 is in contact with this protruding piece 8. 1
It is biased to press it to 0.

When inspecting the reticle 6 placed on the rotary stage 4 for defects, first, the positions of the X and Y stages 1 are measured using the position measuring laser mirrors 2 and 3, and the alignment of the reticle 6 is performed. By detecting the reference mark (not shown), it is possible to determine how far the reticle 6 is deviated from the reference in the X, Y directions (horizontal direction), Z direction (vertical direction), and θ direction (rotational direction). detect,
The X, Y stage 1 is moved according to the detected value, and the piston 10 of the drive mechanism 9 is operated to rotate the rotary stage 4 to position the reticle 6 so that the value in the front and back direction falls within a certain range. By feeding back the deviations of the values in each direction from the reference values to the defect inspection staff and correcting them, reticle defect inspection can be performed with more accurate positional relationships.

Incidentally, since the X, Y stage 1 is required to have responsiveness during movement, it is required to be lightweight and to be processed with high precision. For this reason, X, Y stage 1
is molded from aluminum alloy.

However, since aluminum alloy has a large linear expansion coefficient of 22.8×10 ^-6 /°C, it expands and contracts when there is a change in ambient temperature, resulting in a change in the distance between the reticle to be inspected and the measurement surfaces of the laser mirrors 2 and 3. It turns out.

Since the laser position is measured by measuring the distance between a laser interferometer (not shown) and the measurement surfaces of the laser mirrors 2 and 3, changes in the position between the measurement surfaces of the laser mirrors 2 and 3 and the reticle 6 to be inspected will result in measurement errors. This is one of the causes of performance deterioration in a reticle defect inspection device.

Therefore, it is necessary to put the entire device in an expensive thermal barrier and keep the temperature at a temperature change of about ±0.05°C, and the temperature change during defect inspection of a single reticle 6 is kept at about 0.025°C. There is a need.

As an example, 100 as linear expansion of aluminum
The displacement due to a temperature change of 0.025℃ for mm is
100×22.8×10 ^-6 ×0.025≒0.00005 [mm] = 0.05 [μm]
becomes.

[Purpose of invention]

This invention was made with attention to the above circumstances,
The purpose is to provide a stage device such as a reticle defect inspection device that is not affected by changes in ambient temperature.

[Summary of the idea]

In order to achieve the above object, the present invention arranges a pair of position measurement instruments along the orthogonal direction on the X, Y stage, and provides a support member on the extension line of these pair of measurement instruments. The rotary stage is rotatably supported by a support member, and the rotary stage is made of a material with a low coefficient of expansion, thereby making it possible to prevent measurement errors from occurring.

[Example of idea]

Hereinafter, the present invention will be explained with reference to an embodiment shown in FIGS. 1 to 3. Incidentally, the same parts as those shown in FIG. 4 are given the same numbers, and the explanation thereof will be omitted. In the figure, reference numeral 21 denotes a support member for the rotation stage 4. This support member has a pair of leaf springs 22 and 23 which intersect in an X-shape, and one end of these leaf springs 22 and 23 is connected to an extending portion 4a formed at one corner of the rotary stage 4, respectively. The other end portions are respectively fixed to fixing portions 1a provided on the X and Y stages 1. Then, the intersection of the pair of leaf springs 22 and 23 is set as the rotation center of the rotation stage 4, and this rotation center is the measurement surface of the laser mirrors 2 and 3, which serve as measuring instruments for the position of the X and Y stages 1. It is located at the intersection of the extension lines. Therefore, the rotation center position of the rotation stage 4 is always located on the extension of the measurement surfaces of the laser mirrors 2 and 3 even if the ambient temperature changes. Further, the rotation stage 4 is made of Invar as a material with a low coefficient of expansion. The support member 21 is located on one extension line of the laser mirror 3, and the drive mechanism 9 is located on the other extension line of the laser mirror 3, and is mounted on the X and Y stages 1, respectively.

According to the configuration of this embodiment, the laser mirror 2,
From the measurement plane 3, even if the ambient temperature changes and the X, Y stage 1 is thermally displaced, the distance to the reticle 6 to be inspected will be about 1/20th of the conventional distance.
(The coefficient of linear expansion for Invar is 1.2×10 ^-6 /℃, for aluminum it is 22.8×10 ^-6 /℃) In this way, according to this embodiment, the laser interferometer (not shown) using the position measuring device The measurement error between the measured value of the distance between the laser mirror 2 and the measurement surface of the laser mirrors 2 and 3 and the position of the reticle to be inspected is suppressed slightly, and changes in ambient temperature are less likely to cause deterioration in the performance of the apparatus. Therefore, even if the entire device is placed in a thermal shimber, the reticle to be inspected 6
For example, when using an LE blank, the linear expansion coefficient is 3.7×10 ^-6 /℃, so even if the temperature changes by 0.15℃ for 100 mm, the displacement will be 100×3.7×10 ^-6 ×0.15≒0.00005 [mm]
= 0.05 [μm], and the performance of the thermal multi-chimber is also lower than that of conventional ones.

Note that the present invention is not limited to the above-mentioned embodiment, and the material of the rotation stage 4 is quartz (7
×10 ^-6 /℃), low expansion glass (4×10 ^-6 /℃).
It may be constructed using ceramics (7×10 ^-6 /°C) or titanium (8.4×10 ^-6 /°C).

In addition, it goes without saying that the present invention can be modified in various ways within the scope of its gist.

[Effect of idea]

As explained above, the present invention provides a support member that rotatably supports the rotary stage at the intersection of the extension lines of a pair of measuring instruments for detecting the positions of the X and Y stages, and the rotary stage is mounted on a low expansion member. With this configuration, it is possible to suppress the occurrence of measurement errors to a small extent, and there is an effect that high accuracy is not required for the performance of the thermal multi-chimber, and costs can be reduced.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is a plan view showing a stage device, and FIG.
The figure is a front view showing the support member, FIG. 3 is a perspective view showing a part thereof, and FIG. 4 is a plan view showing a conventional example. 1...X, Y stage, 4...Rotation stage,
2, 3... Measuring device (laser mirror), 21... Support member.

Claims (1)

[Scope of claims for utility model registration] (1) X moving in a direction perpendicular to the horizontal plane,
a Y stage, a pair of laser mirrors for a laser interferometer for measuring the position of the X and Y stages, arranged along two mutually orthogonal sides of the X and Y stages and mounted on the X and Y stages;
a rotary stage mounted on the X, Y stage so as to be rotatable within the horizontal plane about the intersection by a rotatable support member disposed at the intersection on the extension line of the pair of laser mirrors; , a drive mechanism mounted on a Y stage to rotate the rotary stage, and the rotary stage is made of a material with a low coefficient of expansion. (2) The stage device for manufacturing semiconductor devices according to claim 1, wherein the low expansion coefficient material is invar, quartz, low expansion glass, ceramics, titanium, or the like.